The present invention relates broadly to a photographic developing machine, and in particular to an automatic photographic paper and film developing apparatus.
The darkroom and the equipment associated therewith is required to develop photographic paper and film. The darkroom may range from total darkness to room light with safe lights. When the loading and unloading of film and plates in holders of cameras and the processing of films, plates, and paper must be done in the open, these operations are done in the darkroom. The basic darkroom equipment consists of safelights, which are lamp houses with filters to illuminate the room with light of a color which will not fog the sensitive material in a reasonable time and which give maximum visibility consistent with this safety; benches and sinks with running water and drains; tanks and hangers for processing plates and sheet films vertically; tanks for roll films which are usually cylindrical and light-tight and contain a reel onto which the film is wound in a spiral with space convolutions to permit access of the solutions; flat trays for sheet film, plates, and paper sheets and occasionally short roll films: thermometers for determining temperatures of solutions or mixing valves to give water of desired temperature in whioh solutions in tanks are immersed; special multiple tank units for color photography; tanks, trays, or special washers for washing negatives and prints; dryers, ranging from simple clips for hanging negatives in the open air to cabinets having forced warm air, special dryers for prints including simple blotting, paper sheets, and heated flat, drum, or belt dryers, including some which ferrotype (that is, gloss) the prints by drying them in contact with a polished surface; clocks and preset timers; printers and enlargers; print trimmers; and in specialized work, desitometers, printing exposure meters, and focusing devices.
For professional processing of negatives, positives, and reversal positives, both black-and-white and color, and for processing prints on a large scale (for example, in the photofinishing industry) continuous film and roll-paper-processing machines and automatic or semiautomatic printers for contact printing or enlarging onto sheets of rolls of paper are used. Continuous machines are made for processing sheet film and x-ray negatives in sheet form on a large scale, and many continuous processing roll-film or sheet machines have been designed for special purposes, such as aerial photography, microfilming, scientific recording, drawing reproduction, and motion picture film. Roller transport processors are made for rapid stabilization processing of paper prints, especially for papers with incorporated developers. In drum processors, prints are wrapped about a drum revolving rapidly in the solution. However, for the small scale film processor or the amateur photographer/developer, automatic photographic developing equipment is neither available or economically practical. The present invention provides an automatic photographic paper and film developing apparatus for the small scale film developer.